The United States is quietly rushing dozens of Hellfire missiles and low-tech surveillance drones to Iraq to help government forces combat an explosion of violence by an al-Qaida-backed insurgency that is gaining territory in both western Iraq and neighboring Syria.

The move follows an appeal for help in battling the extremist group by Iraqi Prime Minister Nouri al-Maliki, who met with President Barack Obama in Washington last month.

But some military experts question whether the patchwork response will be sufficient to reverse the sharp downturn in security that has already led to the deaths of more than 8,000 Iraqis this year, 952 of them Iraqi security force members, according to the United Nations, the highest level of violence since 2008.

Al-Qaida's regional affiliate, the Islamic State in Iraq and Syria, has become a potent force in northern and western Iraq. Riding in armed convoys, the group has intimidated towns, assassinated local officials and, in an episode last week, used suicide bombers and hidden explosives to kill the commander of the Iraqi army's 7th Division and more than a dozen of his officers and soldiers as they raided an al-Qaida training camp near Rutbah.

Three bombings on Christmas in Christian areas of Baghdad, which killed more than two dozen people, bore the hallmarks of a al-Qaida operation.

The surge in violence stands in sharp contrast to earlier assurances from senior Obama administration officials that Iraq was on the right path, despite the failure of U.S. and Iraqi officials in 2011 to negotiate an agreement for a limited number of U.S. forces to remain in Iraq.

Iraq's foreign minister has floated the idea of having U.S.-operated, armed Predator or Reaper drones respond to the expanding militant network. But al-Maliki, who is positioning himself to run for a third term as prime minister and who is sensitive to nationalist sentiment at home, has not formally requested such intervention.

The idea of carrying out such drone attacks, which might prompt the question of whether the Obama administration has succeeded in bringing the Iraq War to what the president has called a "responsible end," also appears to have no support in the White House.

"We have not received a formal request for U.S.-operated armed drones operating over Iraq, nor are we planning to divert armed ISR over Iraq," said Bernadette Meehan, a spokeswoman for the National Security Council, referring to intelligence, surveillance and reconnaissance missions.

For now, the new lethal aid from the United States includes a shipment of 75 Hellfire missiles, which were delivered to Iraq last week. The weapons are strapped beneath the wings of small Cessna turboprop planes and fired at militant camps with the CIA secretly providing targeting assistance.